<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        .warp {
            background-color: yellow;
            display: flex;
        }
        
        .warp div {
            width: 100px;
            height: 100px;
            border: 2px solid #f00;
            float: right;
        }
        
        .warp2 {
            background-color: aqua;
            display: inline-flex;
        }
        
        .warp2 span {
            width: 100px;
            height: 100px;
            border: 2px solid #f00;
        }
    </style>
</head>

<body>
    <div class="warp">
        <div>box1</div>
        <div>box2</div>
        <div>box3</div>
    </div>

    <div class="warp2">
        <span>box1</span>
        <span>box2</span>
        <span>box3</span>
    </div>

</body>

</html>